Arbitrary Infinite Loop

Why do I get an Infinite Loop error on a node that’s not even connected?

This happens only in editor (not standalone) after 2-3 minutes of gameplay.
Sometimes I get Infinite Loop on other completely unrelated locations like setting a bool variable or on functionality that requires keyboard input which, at the moment, is not triggered.

The blueprint execution time per frame is somewhere between 1ms and 3ms, so I guess the Infinite Loop is not caused by too many instructions, but I have upped the limit to 10 000 000, just in case (didn’t do anything).

Any hints would be appreciated.